Oh my god really.. Project manager.? more like project idiot.
Im sorry to tell you but the warranty is invalid, and the bath has now lost its strength as the roll top is designed to hold it solid.
So its now scap.
I hope you didn't pay them, if there still there kick them of site, and if you did paid ask for refund or go to small claims court, talk to trading standards, and most of all take photos lots of them.
Ask friends if they have used a plumber bathroom fitter and use them.